Well casing scraper



NOV. 2, .v EMANUEL WELL CASING SCRAPER Filed May 4. 1951 I N V EN TOR.

T Toe/wey.

WNCENT EMANUEL,

Il l HMI WELL CASING SCRAPER tes Patent() Vincent Emanuel, Arcadia, Calif., assigner to Grant Oil` Tool Company, Los Angeles, Calif., a corporation of California Application May 4, l1951, Serial No. 224,463 8 Claims. (Cl. 16d- 173) a well, and a number of wall engaging scraping members removably carried by and movable with the body. The invention is directed particularly to the provision in such a tool of improved means for positively retaining the scraping members to the body. In certain broad respects, the present invention may be considered to beV v an application of the general type of retaining arrangement shown in copending application Serial No. 224,568 ledJune 5, 1951 by Henry Salvatori and Virgil R. Douglas, and owned by the assignee of thisapplication.

An object of the invention is to so mount the scraping members to the body as to permit their easy removal and replacement, while at the same time electively maintaining them against undesired displacement relative to the body in use. Specifically, I employ for attaching each scraping member to the body a specially formed retaining element mounted by the body for sliding movement between an active position, in which it positively holds the associated scraper to the body, and a retracted position in which the scraper is freely removable. Preferably, the scraper member has a pair of integral projections or flanges extending 'across its opposite ends and adapted to intert with and be confined by the body and retaining element respectively, to hold the` scraper `to the body.

A further feature ofthe invention has to do with the provision of improvedmeans forV locking such a retaining element in its active scraper holding position. For this purpose, I may employ in conjunction with each retaining element an associated locking element attachable to the body in the retracting path of the retaining,

element to positively block its retraction from holding position.l The locking element may be interposed between and directly engage boththe retaining element and an opposed portion of the body, to maintain the retaining element in holding position independently of any strain on the fasteners which may be employed for attaching the two elements to the body.

To attain a -most effective scraping action, eachof the scraper members is preferably urged outwardly against the well casing bya plurality of springsy interposed between the body ,and member. A particular featurerof the invention involves the specialv construction of the device in a manner permitting variation of the force exerted by these springs. Specifically, I attain a regulation of the spring force by providing for a variation inthe number of individual springs acting against each scraper. In this connection, it is noted that for a proper distribution of the spring force, to effectively stabilize the scraper'members, at least four springs should bear against each member in all conditions of the apparatus.

Consequently, in order to permit a variation of the spring force, I find it extremely important that the apparatus be adapted to receive a number of springs greater than four for each scraper.

The above and other features and objects of the present invention will be better understood from the following detailed description of the typical embodiment illustrated in the accompanying drawing, in which: v

Fig. l is a view showing a casing scraper embodying the invention lowered to operative position in a well;

-vidual rectangular recesses 23 in the body.

2,693,239 'Patented Nov. 2, 1954 Fig. 2 is an enlarged fragmentary vertical section through one of the scraper members of the device;

Figs. 3 and 4 are enlarged horizontal sections taken on lines 3--3 and 4-4 respectively of Fig. l;

Fig. 5 is a fragmentary horizontal section taken on line 5-5 of Fig. 2; and

Fig. 6 is an enlarged exploded perspectivey view of one of the scraper retaining elements and the associated locking element.

The illustrated casing scraping device 10 includes a vertically elongated body 11 to be lowered into a well casing 12, and carrying a number of casing engaging scraper members '13. Body 11 has a threaded portion 14 at its upper end by which it is connectable to the lower end of a suspending and controlling tool string 15. Adjacent its upper threaded portion 14, the body may have a rst cylindrical portion 16, beneath which is formed a second and somewhat enlarged diameter cylindrical portion 17 to which the various scraper members 13 are mounted. As seen in Figs. 3 and 4, the body may contain a central bore 18 extending vertically along its entire length.

The scraper members 13 are preferably arranged in l face 19 having a series of slightly inclined vertically* spaced casing engaging teeth 20. Extending across its upper and lower ends, each scraper member 13 has a pair of reduced thickness flanges or projections 21 and 22, by which it is retained to the body 11.

The Scrapers. 13 are partially received within indi- Across the lower end of each recess 23, the body is undercut at 24 to receive and retain the lower flange 22 of the corresponding scraper. The upper ange 21 of the scraper is confined by a retaining element 25, whose lower end portion is undercut at 26 to receive the flange. Flanges 21 and 22 are of a thickness less than the spaces within which they are confined, to permit limited movement of the scraper member radially of body 11. The scraper member is urged radially outwardly against the casing by a number of coil springs 27 received within individual recesses 28 in the back of the scraper member and bearing against the opposed portions of the body. Preferably, each scraper member contains a number of recesses greater than four, as for instance four pairs as shown, so that the spring tension may be adjusted by removal or replacement of one or more springs, while always maintaining the scraper stabilized by a minimum of four springs.

Each retaining element 25 is received within an upper body recess 29 opening into and forming an upper reduced dimension extension of the corresponding scraper receiving recess 23. As best seen in Figs. 3 and 6, the retaining element -has a pairV of laterally projecting flange portions 30 at its opposite sides slidably received within a lpair of grooves or undercuts 31 inthe walls of recess 29 to form a sliding connection guiding the element for vertical sliding movement toward and away from its illustrated scraper holding position. As will be understond, the undercutting'of body 11 at 31 forms on the bodyvtwo radially inwardly facing` shoulders or surfaces 11.1. which engage flanges 30 of the retaining element to hold the retaining element against outward displacement from the body. .The retaining element is fastened in holding position by a bolt 32, extending through the element andv into the body. An essentially rectangular 'locking element 33 is receivable within upper recess 29 transverse shoulder or facev 135 formed. on1hebody..at the upper end of upper recess 29.

While mounting or removing one of the scraper members 13, the corresponding locking velement 33 is removed from'the body, so thatt-he retaining 'element 25 .is-sldable upwardlyfwithin recess 29f-away fromits .illustrated holding position. After a scraper member'has been-properly located within recess"`23, downward movement of retaining element v25 coniinesthe upper`flange`.21 of the scraper member in a manner such thatthebodyfitself, acting independently vof fastener 32, prevents outward removal of the member 'fromthe body. vLocking .element 33 may then be `positioned above element 25 to prevent .its upward retracting movement. It -visparticularly noted "that by 'virtue' of "the formation of the upper `and lower faces of the locking element, and the faces on the. body wall of casing 12. 4`.Springs 27 urge the scraping members into engagement with Vthe casing, so that teeth 20 are caused by vertical reciprocation of the `device to remove anycement, parain, .or the like from the casing. By virtue of the. unique'manner of mounting `scraper members 13, .any displacing forces exerted against the scrapingrnembers in use are taken by body4 11. and elements 25 and 33, rather than by the .elements mountingV screws 32 .and .3.4. That is, the sliding-interengagement of .element 25.and the body retains that element to the body .independently of screw 32. Also, locking element 33 prevents upward movement .of .element 2,5, without the exertion of .any upward force against screws 32 or 33.

If it becomes desirable to vary. theA force .with which scraper membersl13 .are urged outwardly against the casing, one or more. of-the springs 27 may beremoved or added to attain/.the desired condition. However, to maintaina properly distributed force against the casing, the nlumber of springs should at .all times be atleast four.

Ic aim:

...ment in.said..second .recess .havinglateral flanges lreceived in grooves in the body to.. mount the retaining element l. A well scraping tool. comprising, a .body to be l lowered into a well and containing a first recess at one side, a scraper. member lpartially received in said recess and having a .wall engaging and .scraping portion at an outer side facing away from the body, said body containing a second and reduced' dimension recess openinginto said lirst recess, a retainingelemen means forming a sliding connection mounting said retaining element in said second recess for sliding ,movement toward and away from a position of holding engagement'with the scraper member, said meansl forming the slidingconnection including shouldermeans on the body retaining said element to the bodyA in said position v-of holding engagementrwith `the.scraper, saidretainingelement and body ,havingportions intertting with .the scraper member when the retaining Aelement is in said holding position land acting to positively retain kthe member to the body andagainst turning from thecondition in which said scraping portion of the member is directed outwardly, a rigid locking element removably positioned in said second recess in the retracting path ofsaidretaining element away from said holding .position,.and a fastener removablyfastening said locking element to the bodyin said second recess and in said retracting path of the retaining elementsaid body forming an integral shoulderat the end of said second recess away from said first recess and engaging said locking element so that forces tending to retract said retaining element are transmitted through the locking element to said body.

2. A well scraping tool comprising a body to 'be lowered into a well and containing a rst rectangular recess at one side,a rectangular scraper'memberpar- .tially received in said .recess and having Va wall engaging and scraping portion at an outeriside facing awayfrom the body, said scraper member having a pair of reduced `'thickness flanges extending across'its-opposite ends, .said body containing a-second and reduced.-.dimensionrecess opening into one end of said iirst recess, a retaining elefor sliding movement toward and away from a position of holding engagement with the scraper member, said retaining element and body being undercut at opposite ends of said rst recess to receive and retain said scraper member flanges, said retaining element being disengageable from the body by. sliding movement into said rst recess, a rigid locking element removably positioned in said second recess in the retracting path of said retaining element'away from said holding position, ,and a screw extending through said locking element and into said body .to removably fasten .said locking element to the body in said retracting path of the retaining element, said body forming 4an integral vshoulder at the end of said second recess away from said rst recess and engaging said locking element so that forces tending to retract said retaining element aretransmitted-through .the .locking element to saidbody.

3. A well scraping .tool comprising 4a body 'to ybe lowered into a well and containinga iirst recessatone side, a scraper member partially received-in said ,recess andhaving a -wall engaging and scraping portion at an outer sidev facing away .from .the 4body,.said body containing a second and `reduced dimensionessentially rectangular. recess opening into said .rst .recess,.an essentially rectangular Yretaining element, means forming a sliding connection mounting .said retaining element insaid second recess for sliding .movement tow-ard and away from a position ofholding engagement withthescraper'member,

lsaid means forming the .slidingconnection ,including .overlapping and .received outwardly of different mounting portions of the scrapermember when vthe retaining element is in said holding position `and .acting tov positively retain the member to thebody and. against turning from lthe condition in which said scraping .portionof the member .is directed outwardly,said..scraper member V'being free -for limited :movement outwardly .away..from. .the body when retained, by the .body and retaining element, a plurality vof springs..interp.o.sed between-.thebodypand scraper member and urgingthe. member. outwardly away from the body, tsaid .retainingelementbeing V.disengageable from; the body by ..slidingmovementintosaid'rfirst recess, an essentially.-1:ectangular .rigidlocking -element receivable in said second recess, said lockingielement being interposed between -and :engaging the retaining element and anopposed shoulder.. formed -on the-body at an end .ofsaidsecond .recess `to .prevent movement-of the retaining element from. said .holding-position,.and'. a pair of screws extending .through said retaining element and said locking elementrespectively and into the body .to removably fasten said elements insaid second recess.

v 4. .A Wellscraper .comprising...abody to-beflowered to a well, ascraper -membercarried at. a side .of-the body and'havinga .wall-engaging. and-scraping -portion .at an. outer side .facing-.away.from-.the` body, va retaining .with .the'scraper membensaid meansformingthe sliding connection includingshoulder means .on the body-retainingsaid element to the body in'said Vposition of holding .engagement with the scraper, said retaining element and body having portions intertting-with the scraper-member at different locations ywhen lthe retaining-element is in said `holding position andacting to retain thefmember to the body andto maintain-the member Vagainst turning 'from lthe condition :in-whichfsaid'scraping4 portion `ofthe vmember is directed 'away v'from `the body, said scraper 'member being lremovable from the body when'lthe retaining element is slidably ymoved away lfrom Isaid holding position, a rigid lockingelement attachable to the lbody in the path of the retaining element away vfrom said holding position to maintain-the retaining element in said position, and a.fastener in. addition to said.retaining andA locking elements lremovably fastening said locking -element to .the body in'said path Vof .theretaining element,

said bodyhaving an integral shoulder engaging` said locking element ata. side .opposite :the .side at whichfsaid lockingelementnengages ,the...retaining,.element so; that forces tending to displace the retaining element to retracted position are transmitted through the locking element to the body.

5. A well scraper comprising a body to be lowered into a well, a scraper member carried at a side of the body and having a wall engaging and scraping portion at an outer side facing away from the body, a retaining element, means forming a sliding connection mounting said retaining element to the body for sliding movement toward and away from a position of holding engagement with the scraper member, said means forming the sliding connection including shoulder means on the body retain ing said element to the body in said position of holding engagement with the scraper, said retaining element and body having portions intertting with the scraper member at different locations when the retaining element is in said holding position and acting to retain the member to the body and to maintain the member against turning from the condition in which said scraping portion of the member is directed away from the body, said scraper member being removable from the body when the retaining element is slidably moved away from said holding position, a rigid locking element attachable to the body in the path of the retaining element away from said holding position to maintain the retaining element in said position, said body having an integral shoulder engaging said locking element at a side opposite its point of engagement with the retaining element and at a location alined with said point of engagement in the direction of said path so that forces tending to displace the retaining element to retracted position are transmitted directly through the locking element to the body.

6. A well scraper as recited in claim 5, in which said locking element has a pair of oppositely facing parallel surfaces extending in planes perpendicular to the retracting path of said retaining element and abutting against the retaining element and body respectively to transmit said forces through the locking element.

7. A well scraper comprising a body to be lowered into a well, a screper member carried at a side of the body and having a Wall engaging and scraping portion at an outer side facing away from the body, a retaining element, a sliding connection mounting said retaining element to the body for sliding movement toward and away from a position of holding engagement with the scraper member, said sliding connection including shoulder means on the body retaining said element to the body in said position of holding engagement with the scraper, said retaining element and body having portions interlitting with the scraper member at different locations when the retaining element is in said holding position and acting to retain the member to the body and to maintain the member against turning from the condition in which said scraping portion of the member is directed away from the body, said body and retaining element permitting limited movement of the scraper member radially of the body, spring means yieldingly urging said member radially outwardly, said scraper member being removable from the body when the retaining element is slidably moved away from said holding position, a rigid locking element attachable to the body in the path of the retaining element away from said holding position to maintain the retaining element in said position, and a fastener attaching said locking element to the body, said body having an integral portion engaging said locking element and acting independently of said fastener to prevent any movement of the locking element as a result of forces exerted thereagainst by said retaining element, whereby said forces are transmitted substantially entirely to said body without excessive strain on the fastener, said portion of the body including a body shoulder engaging the locking element at a side opposite its point of engagement with the retaining element.

8. A well scraper as recited in claim 4, including a second fastener acting to attach said retaining element to the body in said holding position.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,121,573 Wetzel Dec. 15, 1914 2,052,174 Hamilton Aug. 25, 1936 2,121,888 Smith lune 28, 1938 2,260,366 Childs Oct. 28, 1941 2,275,939 Baker Mar, l0, 1942 2,602,515 Baker et al. July 8, 1952 

